Stent overlap point markers

ABSTRACT

A medical device and method of providing same, comprises a first stent body and a second stent body wherein the medical device is formed when the at least one first marker portion and the at least one second marker portion of the stent bodies are positioned in a predetermined alignment wherein the first stent body and the second stent body are aligned along substantially the same longitudinal axis and at least a portion of the first end region and at least a portion of the second end region of the respective stent bodies are overlappingly arranged to provide the medical device with a longitudinal length that is less than the sum of the first stent body length and the second stent body length.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not Applicable

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH

Not Applicable

BACKGROUND OF THE INVENTION

Stents, grafts, stent-grafts, vena cava filters and similar implantablemedical devices, collectively referred to hereinafter as stents, areradially expandable endoprostheses which are typically intravascularimplants capable of being implanted transluminally and enlarged radiallyafter being introduced percutaneously. Stents may be implanted in avariety of body lumens or vessels such as within the vascular system,urinary tracts, bile ducts, etc. Stents may be used to reinforce bodyvessels and to prevent restenosis following angioplasty in the vascularsystem. They may be self-expanding, expanded by an internal radialforce, such as when mounted on a balloon, or a combination ofself-expanding and balloon expandable.

Balloon expandable stents are typically disposed about a balloon whichmust be positioned and inflated to expand the stent radially outward.Self-expanding stents expand into place when unconstrained, withoutrequiring assistance from a balloon. Some stents may be characterized ashybrid stents which have some characteristics of both self-expandableand balloon expandable stents.

Typically, a stent or other endoluminal prosthesis is implanted in avessel at the site of a stenosis or aneurysm by so-called “minimallyinvasive techniques” in which the stent is compressed radially inwardsand is delivered by a catheter to the site where it is required. Whenthe stent is positioned at the correct location, the stent is caused orallowed to expand to a predetermined diameter in the vessel and thecatheter is withdrawn.

In the past, stents have been generally tubular but have been composedof many configurations and have been made of many materials, includingmetals and plastic. Ordinary metals such as stainless steel have beenused as have shape memory metals such as Nitinol and the like. Stentshave also been made of bio-absorbable plastic materials. Stents havebeen formed from wire, tube stock, etc. Stents have also been made fromsheets of material which are rolled.

In order to better provide for the precise placement of the stent withina body location some stents include radiopaque materials which may bedetected through the use of fluoroscopy. In this manner the position ofthe stent within a body vessel may be identified. Radiopaque materialsare well known and have been incorporated into stents in several ways.For example, in U.S. Pat. No. 6,402,777 rivets made of radiopaquematerial are positioned in stent openings; in U.S. Pat. No. 5,725,572 astent is said to include a radiopaque material affixed to undeformedcomponents at the distal or proximal end of the stent; and in U.S. Pat.No. 5,954,743 at least partially plating a stent with radiopaquematerial is described.

Stents are known to have a variety of shapes sizes and structuralfeatures. For example, stents may have a variety of lengths, diameters,cell configurations, end effects, etc. Stents may be branched orsegmented for use in a vessel bifurcation. Such stents may also includeone or more ports or crowns where additional stent bodies may beengaged. Some examples of stents having at least some of the structuralfeatures mentioned above are described in the following references: U.S.Pat. App. Ser. No. 10/084,766; U.S. Pat. App. Ser. No. 10/083,707; U.S.Pat. App. Ser. No. 10/083,711.

In some cases it is necessary or desirable to place multiple stents, sothat the stents are arranged in an end to end manner within a vessel orother body space. Recent studies have shown that in some cases, such asin some applications of drug coated stents, prevention of restenosis maybe improved when the ends of adjacent stents are made to overlap oneanother according to a predetermined alignment. Currently however,precise multiple stent alignment wherein the overlapping stents have apreferred length of stent end overlap is difficult to achieve.

All US patents and applications and all other published documentsreferred to anywhere in this application are incorporated herein byreference in their entirety.

Without limiting the scope of the invention a brief summary of some ofthe claimed embodiments of the invention is set forth below. Additionaldetails of the summarized embodiments of the invention and/or additionalembodiments of the invention may be found in the Detailed Description ofthe Invention below.

A brief abstract of the technical disclosure in the specification isprovided as well only for the purposes of complying with 37 C.F.R. 1.72.The abstract is not intended to be used for interpreting the scope ofthe claims.

BRIEF SUMMARY OF THE INVENTION

The present invention is embodied in a variety of different forms. Forexample, some embodiments of the invention are directed to methods andsystems for treating a stenosis by implanting at least two stents orstent bodies into a vessel, wherein the stent bodies are placed in anoverlapping relationship. In order to provide the resulting stentassembly with stent bodies having a desired overlapping configuration,the respective stent ends are provided with one or more alignmentmarkers that allow the stent end to be overlappingly aligned in a veryprecise manner. The markers may have a greater or lesser degree ofradiopacity than the surrounding end regions. In at least one embodimentthe markers and/or other portions of the stent bodies may be MRIcompatible.

In the various embodiments of the invention, the manner and degree, orlength, of stent overlap may be varied. For example, in some embodimentsthe overlapping stent bodies are configured such that when they areoverlapped, at least a portion of one stent is positioned radiallywithin the lumen defined by another stent. In some embodiments theoverlapping stent bodies are configured such that when they areoverlapped, the stent bodies are longitudinally adjacent to one another.In at least one embodiment in the region where the longitudinallyadjacent stent bodies are overlapped, the diameter of each stent body issubstantially the same.

In some embodiments the invention is directed to a bifurcated stent thatdefines a side opening, crown or branch. The branch may be configured tooverlap, or be overlapped by a secondary stent body.

In some embodiments at least a portion of at least one of the stents isdrug coated. In at least one embodiment, the end of at least one stentis coated. In at least one embodiment one or more ends of adjacentstents are selectively coated. By selectively coating the ends ofadjacent stents, the overlapping ends of the stents may be provided withamounts or concentrations of coating such that overlapping ends of thestent bodies provide a coated interface with the surrounding vessel thatis substantially the same as the non-overlapped coated portions of thestent bodies. In at least one embodiment the ends of the stent bodiesmay be selectively coated to have different proportions of the drugcoating relative to the proportion of coating on the remaining portionsof the respective stent bodies. In at least one embodiment theproportionally amount of drug coating on the overlapped portion of thestents may be greater than or less than the amount of drug coatingelsewhere on the stent bodies.

In at least one embodiment at least a portion of the adjacent ends ofthe stent bodies are engaged to one another. In at least one embodimentoverlap of the ends of the stents is by frictional, mechanical,electromagnetic, chemical, or other engagement. In at least oneembodiment the at least one stent end is uniquely keyed to the end of anadjacent stent.

These and other embodiments which characterize the invention are pointedout with particularity in the claims annexed hereto and forming a parthereof. However, for a better understanding of the invention, itsadvantages and objectives obtained by its use, reference should be madeto the drawings which form a further part hereof and the accompanyingdescriptive matter, in which there is illustrated and describedembodiments of the invention.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

A detailed description of the invention is hereafter described withspecific reference being made to the drawings.

FIG. 1 is a side view of an embodiment of the invention.

FIG. 2 is a side view of the embodiment shown in FIG. 1 wherein theindividual stent bodies are shown separated.

FIG. 3 is a cross-sectional view of an embodiment of the invention.

FIG. 4 is a cross-sectional view of an embodiment of the invention.

FIG. 5 is a close-up partial side view of an embodiment of the inventionillustrating an example alignment of markers.

FIG. 6 is a close-up partial side view of an embodiment of the inventionillustrating an example alignment of markers.

FIG. 7 is a close-up side view of an embodiment of the invention whereinthe ends of the assembly are engaged to one another.

FIG. 8 is a close-up side view of an embodiment of the invention whereinthe ends of the assembly are engaged to one another.

FIG. 9 is a side view of an embodiment of the invention.

FIG. 10 is a close-up side view of an embodiment of the inventionwherein the assembly includes a coating.

FIG. 11 is a close-up side view of an embodiment of the inventionwherein the assembly is includes a coating.

DETAILED DESCRIPTION OF THE INVENTION

While this invention may be embodied in many different forms, there aredescribed in detail herein specific preferred embodiments of theinvention. This description is an exemplification of the principles ofthe invention and is not intended to limit the invention to theparticular embodiments illustrated.

For the purposes of this disclosure, like reference numerals in thefigures shall refer to like features unless otherwise indicated.

As indicated above, the present invention is directed to a variety ofdifferent embodiments. An example of one such embodiment is shown inFIG. 1 wherein a stent assembly, indicated generally at 10, is shown. Invarious embodiments of the invention stent assembly 10 may be comprisedof two or more stents or stent bodies 12 and 14 such as is shown in FIG.2. Stent bodies may be any sort of implantable prosthesis such asstents, grafts, stent-grafts, vena cava filters, etc.

Stent bodies 12 and 14 may be balloon expandable stents,self-expandable, or hybrid expandable. Stent bodies 12 and 14 may besingle layer or multi-layer devices. The bodies may have the same ordifferent construction and expansion characteristics. In someembodiments, one or more of the stent bodies 12 and 14 may be at leastpartially constructed from a shape memory metal such as nitinol (Ni—Ti),or a shape-memory polymer.

To form stent assembly 10, stent bodies 12 and 14 are positionedtogether such that at least a portion of their respective end regions 16and 18 at least partially overlap one another. As indicated above, themanner and degree of end overlap may be varied. For example, in theembodiment shown in FIG. 1, the end regions 16 and 18 of each stent body12 and 14 have a similar and complimentary configuration which allows atleast a portion of the end regions 16 and 18 to interpenetrate oneanother. Where the stent bodies 12 and 14 are aligned along the samelongitudinal axis 15 such as is shown in FIG. 2, the assembly 10 will beprovided with substantially the same outer diameter through out itslongitudinal length.

However, it is recognized that the overlap of end regions 16 and 18 neednot always be longitudinally and/or radially aligned. For example, insome cases the stent bodies 16 and 18 may be aligned and overlapped tosuccessfully form assembly 10 even though the stent bodies 16 and 18have different longitudinal axes, represented as reference numerals 15 aand 15 b respectively, such as is shown in FIG. 3. In another embodimentillustrated in FIG. 4, end region 18 of stent body 14 may be positionedradially within end region 16 of stent body 12. In the embodiment shownin FIG. 4 the stent bodies 12 and 14 may have substantially the samelongitudinal axis 15, but in the portion of the assembly 10 defined bythe overlapping end regions 16 an 18 the diameter of stent 12 is lessthan the diameter of stent 16.

Depending on the particular construction of the stent bodies, otherconfigurations may be possible. Such configurations of overlap madepossible by the present invention and are incorporated within its scope.

In order to properly control the alignment and length of overlap ofstent bodies 12 and 14, the stents, or portions thereof may includemarker portions 28 that allow the end regions 16 and 18 to be visuallyor otherwise aligned, such as is shown in the various figures.

Markers 28 are preferably constructed from materials that are visuallydistinct or otherwise detectable. For example, in some embodiments themarkers are at least partially constructed from one or more radiopaquematerials such as radiopaque metals and/or radiopaque polymers. Thoughradiopacity is the characteristic that shall be discussed in detail, itshould be understood that in some embodiments, markers 28 may be MRIcompatible and detectable thereby, X-ray detectable, radio luminescent,may be visually distinct to the naked eye, etc.

In some cases the markers 28 are constructed of radiopaque material tomake the markers 28 more visible during fluoroscopy or similarprocedures, however in some embodiments, particularly those wherein theend regions 16 and 18 or other portions of the stents 12 and 14 arethemselves radiopaque, the markers 28 may be selected to be more or lessradiopaque than the surrounding portions of the stents.

The presence of radiopaque markers 28 on the end regions 16 and 18 ofthe stent bodies 12 and 14, allows the operator or surgeon to positionthe second stent 14 in relation to the deployed first stent 12 in aprecise overlapping alignment configuration, such as any of thosedescribed above. The markers located in their respective end regions 16and 18 may be placed in overlapping alignment or some other recognizableconfiguration or pattern to ensure proper alignment of the stent bodies12 and 14. In this manner the markers 28 act as guides to ensure thatthe proper overlapping arrangement of the end regions 16 and 18 has beenachieved.

The extent end regions 16 and 18 are overlapped may depend on a varietyof circumstances. For example, where the assembly 10 is utilized in acoronary vessel the length of overlap between the stent end regions 16and 18 is between about 0.25 mm to about 10 mm, however when theassembly is placed in a peripheral vessel, the overlap may be as greatas 20 mm.

The particular material, shape, arrangement, placement, etc. of markers28 on the end regions 16 and 18 may be any desired. For example, themarkers 28 may be at least a portion of one or more individual stentmembers or be positioned extraneously thereon. The markers may comprisea radiopaque material that is more or less radiopaque than that of thesurrounding stent body or bodies 12 and 14. The markers 28 may be aninherent portion of the end regions 16 and 18. Alternatively, the endregions 16 and 18 or portions thereof may be selectively or entirelycoated, plated, or otherwise provided with one or more markers 28, suchas for example by providing and end region with one or more radiopaquerivets, welds, wires or other structures.

In some embodiments the markers 28 in the completed assembly 10 may beadjacent to one another in a substantially radial, circumferential,longitudinal or other manner. In some embodiments, the markers 28 may bepositioned such that markers are spaced apart from one another accordingto a desired pattern, an example of which being illustrated in FIG. 5.In another embodiment shown in FIG. 6, the markers 28 are intermittentlyarranged in a pattern about the circumference of the stents 12 and 14,such that when viewed during fluoroscopy the markers 28 appear to formone or more lines, or other patterns. Other configurations andarrangements are possible and are within the scope of this invention.

In the embodiments discussed thus far the formation of assembly 10 isaccomplished by deploying the first stent body 12 into the vessel andthen subsequently deploying the second stent body 14 in proximity to thefirst stent body 12 so that the end regions 16 and 18 overlap in themanner desired. In these embodiments however, the alignment of thestents 12 and 14 within the vessel and any frictional engagement thatmay occur between contacting end regions 16 and 18 may be the primaryforces acting to hold the stents together in precise alignment.

In order to more securely engage end regions 16 and 18 together, someembodiments of the invention employ various engagement mechanisms anddevices to engage end regions 16 and 18 together. For example, in FIG. 7the end regions 16 and 18 may be provided with engagement surfaces 22that provide improved frictional, mechanical, chemical, and/or evenelectromagnetic interface between the end regions 16 and 18 or portionsthereof.

An example of one form of engagement surface(s) 22, is illustrated inthe embodiment shown in FIG. 8, wherein opposing end regions 16 and 18are respectively provided with one or more protrusions 24 and receivingsurfaces 26. In the embodiment shown, the interface of protrusions 24and receiving surfaces 26 may provide increased frictional engagementbetween the regions 16 and 18.

In some embodiments, at least a portion of one or more of theprotrusions 24 and/or receiving surfaces 26 may be constructed of ashape memory material allowing the protrusions 24 and/or surfaces 26 totransform to a preset shape upon exposure to an environmental triggersuch as a predetermined temperature, electric current, pH, etc. In thismanner the protrusions 24 and/or receiving surfaces 26 may by made toactively and mechanically engage one another for improved securement ofthe overlapping regions 16 and 18.

In another example, the engagement surfaces 22 may include a coatingwhich adhesively or otherwise aids in chemical engaging the overlappingsurfaces together.

In yet another example, at least a portion of the end regions 16 and 18,such as engagement surfaces 22, are provided with opposing magneticpolarity to electro-magnetically engage the overlapping surfacestogether.

In some embodiments, the stent bodies 12 and 14 or portions thereof, arebioabsorbable to allow the individual stent bodies 12 and 14 to beremoved from the body or absorbed thereby at a point in time subsequentto placement of the assembly 10.

As indicated above, some embodiments of the invention are directed tobifurcated stent assemblies, an example of which is shown in FIG. 9. Inthe embodiment shown a bifurcated assembly, indicated generally at 10,comprises a first stent body 12 and a second stent body 14. First stentbody 12 defines a side opening 30. In some embodiments, the side opening30 may be further defined by a crown or branch 32 of stent material.

In the embodiment shown in FIG. 9 the side opening 30, and/or crown 32is at least partially defined by one or more markers 28. The secondstent body 14 includes an end region 18 which comprises one or moremarkers 28 as well. In application, after either the first stent body 12or second stent body 14 is delivered to a bifurcation in a vessel orbody lumen, the other body 12 or 14 is positioned adjacent thereto sothat at least a portion of the end region 18 of the second stent body 14and the opening 30 and/or crown 32 of the first stent body 12 areoverlapped. The particular configuration of overlap between stent bodies12 and 14 may include any configuration such as those described above.

When the end region 18 and opening 30 and/or crown 32 are overlapped ina desired configuration, the markers of the respective end region 18 andopening 30 and/or crown 32 will have a predetermined alignment such asis shown in FIGS. 5 and 6. As is shown in FIG. 9, crown 32 defines alongitudinal axis 15 c which the longitudinal axis 15 b of the secondstent body may or may not be aligned with such as in the mannerspreviously described in FIGS. 3 and 4. The overlap of the bodies 12 and14 forming the completed bifurcated assembly 10 of FIG. 9 may include aphysical overlap and/or engagement of the bodies 12 and 14 such as isshown in FIGS. 7 and 8.

In some embodiments, the assembly 10 is at least partially coated with adrug or other substance, the extent that the stent bodies 12 and 14 arecoated with a drug or other coating may also affect the manner anddegree of the stent overlap.

In some embodiments, particularly those wherein one or more of the stentbodies 12 and 14 are include a drug coating or other drug deliverymechanism, the extent or length of the overlap of the end regions 16 and18 may be of particular importance.

Drugs and coatings thereof are well known. The application of such acoating to a stent allows the stent to deliver the drug directly to adesired location within the vessel. However, in many applications it maybe of importance to ensure that the concentration, amount, or exposureof the drug along a given length of the stent is substantiallyconsistent. Thus, in some embodiments of the present invention, such asis shown in FIG. 10, the assembly 10 employs a coating 21 of drug thatextends across the overlapping end regions 16 and 18. In order to ensurethat the exposure of the drug is substantially the same over the lengthof the assembly, the end regions 16 and 18 are selectively coated to anextent less than adjacent regions of the respective stent bodies 12 and14, such that when regions 16 and 18 are overlapped to form assembly 10the exposure of the coating is substantially equal along the entirecoated length of the assembly 10.

It should be noted, that where a consistent concentration or exposure ofa coating is desired, the end regions 16 and 18 need not be selectivelycoated to an equal proportion. For example, in the embodiment shown inFIG. 11, end region 16 is fully coated (one hundred percent), whereasend region 18 is not at all coated (zero percent). However, the extentof exposure of coating 21 remains substantially constant along thelength of the completed assembly 10. In other embodiments, end regions16 and 18 may be provided with other proportions of coating. In oneexample for instance, end region 16 may be provided with a 75 percentcoating, whereas end region 18 has only 25 percent.

In other embodiments, it may be desired to provide a greater or lesserconcentration or exposure of coating 21. In such embodiments, the endregions 16 and 18 may be selectively coated so that when they areoverlapped to form assembly 10 the concentration of coating at theoverlapped regions 16 and 18 is different than that of the concentrationelsewhere along the length of the assembly 10.

In the various embodiments described above, drug coating 21 may becomprised of any or all of a variety of drugs, genetic material,non-genetic therapeutic agents, cells and/or cellular material, polymercoatings, viruses, retro-viruses, and/or other substances. In someembodiments, coating 21 is at least partially radiopaque.

Some particular examples of materials suitable for use as a coatinginclude but are not limited to: anti-thrombogenic agents such asheparin, heparin derivatives, urokinase, PPack (dextrophenylalanineproline arginine chloromethylketone), etc.; anti-proliferative agentssuch as enoxaprin, angiopeptin, or monoclonal antibodies capable ofblocking smooth muscle cell proliferation, hirudin, acetylsalicylicacid, etc.; anti-inflammatory agents such as dexamethasone,prednisolone, corticosterone, budesonide, estrogen, sulfasalazine,mesalamine, etc.; antineoplastic/antiproliferative/anti-miotic agentssuch as paclitaxel, 5-fluorouracil, cisplatin, vinblastine, vincristine,epothilones, endostatin, angiostatin, thymidine kinase inhibitors, etc.;anesthetic agents such as lidocaine, bupivacaine, ropivacaine, etc.;anti-coagulants such as D-Phe-Pro-Arg chloromethyl keton, an RGDpeptide-containing compound, heparin, antithrombin compounds, plateletreceptor antagonists, anti-thrombin anticodies, anti-platelet receptorantibodies, aspirin, prostaglandin inhibitors, platelet inhibitors, tickantiplatelet peptides, etc.; vascular cell growth promotors such asgrowth factor inhibitors, growth factor receptor antagonists,transcriptional activators, translational promoters, etc.; vascular cellgrowth inhibitors such as growth factor inhibitors, growth factorreceptor antagonists, transcriptional repressors, translationalrepressors, replication inhibitors, inhibitory antibodies, antibodiesdirected against growth factors, bifunctional molecules consisting of agrowth factor and a cytotoxin, bifunctional molecules consisting of anantibody and a cytotoxin, etc.; cholesterol-lowering agents;vasodilating agents; agents which interfere with endogenous vascoactivemechanisms; anti-sense DNA and RNA; DNA coding for anti-sense RNA; DNAcoding for tRNA or rRNA to replace defective or deficient endogenousmolecules; DNA coding for angiogenic factors including growth factorssuch as acidic and basic fibroblast growth factors, vascular endothelialgrowth factor, epidermal growth factor, transforming growth factor α andβ, platelet-derived endothelial growth factor, platelet-derived growthfactor, tumor necrosis factor α, hepatocyte growth factor and insulinlike growth factor; DNA coding for cell cycle inhibitors including CDinhibitors; DNA coding for thymidine kinase (“TK”) and other agentsuseful for interfering with cell proliferation; DNA coding for thefamily of bone morphogenic proteins (“BMP's”) BMP-2, BMP-3, BMP-4,BMP-5, BMP-6 (Vgr-1), BMP-7 (OP-1), BMP-8, BMP-9, BMP-10, BMP-11,BMP-12, BMP-13, BMP-14, BMP-15, BMP-16, and dimeric proteins provided ashomodimers, heterodimers, or combinations thereof, alone or togetherwith other molecules, as well as other associated proteins; cells orportions thereof of human origin (autologous or allogeneic) or from ananimal source (xenogeneic), genetically engineered if desired to deliverproteins of interest at the transplant site; polycarboxylic acids;cellulosic polymers, including cellulose acetate and cellulose nitrate;gelatin; polyvinylpyrrolidone; cross-linked polyvinylpyrrolidone;polyanhydrides including maleic anhydride polymers; polyamides;polyvinyl alcohols; copolymers of vinyl monomers such as EVA; polyvinylethers; polyvinyl aromatics; polyethylene oxides; glycosaminoglycans;polysaccharides; polyesters including polyethylene terephthalate;polyacrylamides; polyethers; polyether sulfone; polycarbonate;polyalkylenes including polypropylene, polyethylene and high molecularweight polyethylene; halogenated polyalkylenes includingpolytetrafluoroethylene; polyurethanes; polyorthoesters; proteins;polypeptides; silicones; siloxane polymers; polylactic acid;polyglycolic acid; polycaprolactone; polyhydroxybutyrate valerate andblends and copolymers thereof; coatings from polymer dispersions such aspolyurethane dispersions (BAYHDROL®, etc.); fibrin; collagen andderivatives thereof; polysaccharides such as celluloses, starches,dextrans, alginates and derivatives; hyaluronic acid; squaleneemulsions; polyacrylic acid, such as HYDROPLUS® available from BostonScientific Corporation, Natick, Mass., and described in U.S. Pat. No.5,091,205, the entire disclosure of which is hereby incorporated hereinby reference; etc.

While the figures included herewith illustrate the relationship betweentwo stent bodies to form the completed assembly, it should be recognizedthat the inventive assembly and the accompanying method for providingsame as described herein may comprise more than two stents or stentbodies overlappingly arranged in similar or different manners.

The above disclosure is intended to be illustrative and not exhaustive.This description will suggest many variations and alternatives to one ofordinary skill in this art. All these alternatives and variations areintended to be included within the scope of the claims where the term“comprising” means “including, but not limited to”. Those familiar withthe art may recognize other equivalents to the specific embodimentsdescribed herein which equivalents are also intended to be encompassedby the claims.

Further, the particular features presented in the dependent claims canbe combined with each other in other manners within the scope of theinvention such that the invention should be recognized as alsospecifically directed to other embodiments having any other possiblecombination of the features of the dependent claims. For instance, forpurposes of claim publication, any dependent claim which follows shouldbe taken as alternatively written in a multiple dependent form from allprior claims which possess all antecedents referenced in such dependentclaim if such multiple dependent format is an accepted format within thejurisdiction (e.g. each claim depending directly from claim 1 should bealternatively taken as depending from all previous claims). Injurisdictions where multiple dependent claim formats are restricted, thefollowing dependent claims should each be also taken as alternativelywritten in each singly dependent claim format which creates a dependencyfrom a prior antecedent-possessing claim other than the specific claimlisted in such dependent claim below.

This completes the description of the preferred and alternateembodiments of the invention. Those skilled in the art may recognizeother equivalents to the specific embodiment described herein whichequivalents are intended to be encompassed by the claims attachedhereto.

1-42. (canceled)
 43. A stent assembly having an assembled state and anunassembled state, the assembly comprising: a plurality of substantiallytubular stent bodies, each stent body having an inner surface, an outersurface, a first end, a second end and a length extending between thefirst end and the second end, the inner surface defining a lumen and theouter surface comprising a drug coating, the drug coating comprising anamount distributed along the length of the stent body, in theunassembled state the stent bodies being spaced apart from one another,in the assembled state the first end of one stent body being engaged toa second end of an adjacent stent body along a common longitudinal axis,the amount of the drug coating on the stent bodies having asubstantially constant distribution along the length of the stent bodiesin the assembled state.
 44. The stent assembly of claim 43 wherein eachstent body further comprises at least one radiopaque marker, the atleast one radiopaque marker positioned at at least one of the first endand second end.
 45. The stent assembly of claim 44 wherein in theassembled state the at least one radiopaque marker of the one stent isimmediately adjacent to the at least one radiopaque marker of theadjacent stent.
 46. The stent assembly of claim 43 wherein each stentbody comprises a radius as measured from the longitudinal axis, theradius of each stent being substantially the same in the assembledstate.
 47. The stent assembly of claim 43 wherein the first end of theone stent body has a first magnetic polarity and the second end of theadjacent stent body has a second magnetic polarity, the first magneticpolarity being substantially opposite the second magnetic polarity. 48.The stent assembly of claim 43 wherein at least one of the stent bodiesis a self-expandable stent.
 49. The stent assembly of claim 43 whereinat least one of the stent bodies is at least partially constructed froma shape-memory material.
 50. The stent assembly of claim 43 wherein atleast one of the stent bodies is a balloon expandable stent.
 51. Thestent assembly of claim 43 wherein at least one of the stent bodies is ahybrid expandable stent.